1. Field of the Invention
This invention pertains generally to hose couplings, and more particularly to plastic couplings for the ends of flexible, resilient hoses of the so-called garden hose type.
2. Description of the Prior Art
Garden hoses made of various forms of rubber and plastic, are generally provided with so-called male and female end couplings by which the hoses are connected to one another, to faucets or spigots supplying liquid thereto, and to nozzles, sprinklers, etc. for dispensing the liquid. On currently marketed hoses such couplings, which are permanently affixed to the hose ends during production of the hose assembly, are generally of two types. In one, threaded male and female couplers of plastic or brass have a barbed stem which is inserted into the hose end. A clamp member, generally of brass, surrounds the external periphery of the hose and urges it into liquid-tight engagement with the stem. In the other, the threaded male and female couplers, generally of brass or the like, include a tubular sleeve which fits over the outer end of the hose. A ferrule, again of brass or the like, is inserted into the hose end and permanently expanded outwardly to urge the hose into liquid-tight engagement with the tubular sleeve.
The hoses tend to bend most sharply immediately adjacent the coupling during normal use and, after repeated flexing, tend to develop cracks around the coupling until they eventually leak and even break completely off of that point. The metallic components are fabricated of relatively thin sections so that they are easily bent out of shape and permanently deformed by being stepped upon or run over by vehicles. As a result, it may be impossible to couple the hose to an appropriate associated male or female coupling unit or, if it can be so coupled, the joint connection may leak.
Metallic couplings of the aforedescribed types are relatively costly to fabricate and assemble. Both the material itself and the forming process are comparatively expensive. The female units comprise two separate pieces which must be assembled before the coupling is affixed to the hose, thereby complicating the assembly process.
It has been found that the hoses themselves tend to have a longer service life than the prior art original couplings. As a result, replacement couplings have been developed which can be applied to a hose end by the user in place of the original factory applied coupling. One such unit comprises a barbed stem for insertion into the hose, with an external clamp, such as a conventional screw clamp, for securing the hose around the stem. Another, as disclosed in U.S. Pat. No. 4,313,628, typically includes an external sleeve adapted to fit over the end of the hose, with a tapered bushing which threads into the hose and spreads or flares it outwardly against the sleeve. Such replacement couplings have not proven entirely satisfactory in that in either type, due to insertion of a member inside the hose, the diameter is effectively reduced and liquid flow is constricted. The external clamp or tapered internal bushing tends to loosen and allow the coupling to leak and eventually to pull apart. With the tapered insert, the stress is concentrated at the widest portion of the insert during assembly and thereafter, creating an area of likely hose failure.